In a photolithography step in manufacturing process of, for example, a semiconductor device, for example, a resist coating treatment of applying a resist solution onto a film to be worked on a wafer surface to form a resist film, exposure processing of applying light in a predetermined pattern to the resist film on the wafer surface to expose the resist film, heating processing of heating the wafer to accelerate the chemical reaction in the exposed resist film (post-exposure baking), developing treatment of developing the heated resist film and the like are performed in sequence to form a predetermined resist pattern in the resist film on the wafer surface. Thereafter, the film to be worked is etched using the resist pattern as a mask and the resist pattern is then removed, whereby a predetermined pattern is formed in the film to be worked.
To contemplate miniaturization of the semiconductor device, the light for the exposure processing in the above-described pattern formation is progressively shortened in wavelength. Only with the method of progressively shortening the wavelength for exposure, however, it is technically difficult to form a semiconductor device having a fine line width, for example, at a level of 32 nm or 45 nm. Hence, it is proposed to form a finer pattern by performing patterning a plurality of times on a film to be worked in the same layer on the wafer surface to miniaturize the semiconductor device (see Patent Document 1).
[Patent Document 1]
Japanese Patent Application Laid-open No. H7-147219